As Fr. Bonaventure Knaebel, OSB, celebrates his 100th birthday he's often asked to look back at his 80 years of monastic life.

Those eight decades have been filled with many assignments. He was a student, a teacher, a pastor, an administrator, spiritual director, manager of Abbey Press, and interim superior at two abbeys.

And as a young man of 36, he was elected archabbot of Saint Meinrad Archabbey. For 11 years (1955-1966), he was the leader of the monastic community, which numbered 197 at the time of his election.

When Fr. Bonaventure is asked about his service to the Saint Meinrad community and to the Church, he reaches for his copy of the Rule of St. Benedict. It is a well-worn, marked-up book, the same one he received from his novice master in 1937.

Service begins with loving God and loving one's neighbor, he says, referring to Chapter 4. Both of those come before love of self, and that guides the monk's life.

Reflecting on his role as superior of the monastic community, Fr. Bonaventure believes he wasn't as prepared as the men who have served as archabbot in more recent times. After joining the monastery in 1938, Fr. Bonaventure continued his studies for the priesthood and was ordained in 1943. He was then sent to The Catholic University of America in Washington, D.C., to earn a master's degree so he could teach mathematics when he returned to Saint Meinrad.

He taught from 1946 until 1955, when he was elected archabbot. During those nine years, he had few opportunities to develop leadership skills. Nonetheless, he accepted the role and moved the community forward.

Under his leadership, Saint Meinrad founded a community in Peru (now closed) and a new abbey in California - Prince of Peace Abbey in Oceanside. The first guest house was built during his tenure and several infrastructure improvements were made, including a water filtration plant and a sewage disposal system.

Also at that time, the abbey was operating Abbey Press, a farm, a coal mine and a quarry. The high school, college and seminary were in place as well, with more than 700 students.

In addition, the Second Vatican Council was under way during Archabbot Bonaventure's tenure. After Vatican II, many of the formal rituals surrounding the office of the archabbot began to fade away.

In the early days, Fr. Bonaventure recalls, "there was much more ritual connected with being abbot. The monks could be kneeling in the choir stalls at 4 o'clock in the morning. When the abbot came in, everybody stood up. They could all be seated in the refectory (dining room), like at breakfast, and if the abbot came in, we all stood up."

Other Vatican II changes included celebrating Mass and the Liturgy of the Hours in English, rather than the traditional Latin. Archabbot Bonaventure asked a group of monks to experiment with praying the Divine Office in English, and in May 1967 it was rolled out to the full community.

The Vatican II changes also allowed Archabbot Bonaventure to appoint a non-priest monk to be in charge of some things, such as the Guest House or Abbey Press. Before that, any leadership role was filled by a priest. "The distinction between priests and brothers has been minimized a great deal. In fact, it was one of the good points, as far as I'm concerned, coming out of Vatican II," he says.

After he resigned as archabbot, Fr. Bonaventure went to Saint Meinrad's mission in Peru. He served there as a missionary from 1974 to 1979.

When he returned, he became pastor of Sacred Heart Parish in Jeffersonville for two years, then pastor of St. Michael Parish in Charlestown for five years. Other assignments included administrator of a Benedictine monastery in Morelia, Mexico, for two years and then at Corpus Christi Abbey in Sandia, TX, for two years.

He also served as chaplain at St. Paul Hermitage in Beech Grove, IN, and then - in his 80s - as administrator of St. Michael Parish in Bradford, IN.

Today Fr. Bonaventure lives in the monastery infirmary. Although he moves slower than he used to and finds it harder to read and hear, he focuses on prayer, reading and doing research into the kingdom of God. "I'm still working on some things," he says.